Load carrying structures are commonly used in concrete forming, in building vertical walls, in lining tunnels with concrete, shoring freshly dug tunnel walls, and the like. With most concrete form work, slip forms are used which are moved along the surface of set concrete. With this type of concrete form work, a supporting structure for the form work is secured to the form work and jacks move the supporting structure in order to advance the form work along the concrete face.
Climbing slip forms are well-known, such as that disclosed in Scharsach, U.S. Pat. No. 2,620,543. He discloses concrete panel forms which are supported by a supporting structure which includes a number of vertical posts attached to the concrete panel forms. Guide rods are secured to the set concrete where the concrete form panels move independently of the guide rods. Jack rods are secured to the guide rods. Jacks are mounted on the supporting posts which engage the jack rods. Operation of the jacks advances the supporting structure. The concrete form panels are advanced simultaneously with advancement of the supporting structure because the concrete form panels are secured to the supporting structure. Like all other slip form concreting apparatus, Scharsach has no provision for permitting the concrete forming panels to remain stationary while the heavy supporting structure for the concrete panels is advanced by the operation of jacks.
In concrete forming and other operations such as lining horizontal tunnels, it is advantageous to have the load carrying panels remain stationary while the supporting structure is advanced and additional load carrying panels attached to and in front of the stationary panels. For example, when concrete form panels are left stationary and new panels attached, the rate of concrete pouring can be varied within broad limits so as to be adapted to other working tasks associated with the concrete pouring operation. In some cases the use of climbing slip forms requires anchoring bolts in the concrete so that the slip forms are not advanced until the concrete has set. Stationary load carrying panels are advantageous for lining horizontal tunnels because the panels remain in position until the concrete has set or the walls of the tunnel are properly shored. Meanwhile, the heavy supporting structure can be advanced with additional panels placed in position, without waiting for the concrete to set so that the same panels may be advanced.
It is therefore an object of the invention to provide apparatus and method for shifting a heavy supporting structure relative to a load carrying structure which remains stationary.
It is a further object of the invention to provide in combination, a heavy supporting structure for a load carrying structure where the heavy supporting structure is advanced relative to the load carrying structure by use of jacks engaging jack rods which are secured to the load carrying structure.
It is another object of the invention to provide a method of concreting where the load carrying panels remain stationary during advancement of the concrete pouring operation.
It is yet another object of the invention to provide method and apparatus for lining tunnels with concrete and to provide methods of shoring tunnels to guard against landslide.